First cut at infobars on Mac. These are not expected to be...

chrome/browser/cocoa/infobar.h

+// Copyright (c) 2009 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CHROME_BROWSER_COCOA_INFOBAR_H_
+#define CHROME_BROWSER_COCOA_INFOBAR_H_
+
+#include "base/logging.h"  // for DCHECK
+
+@class InfoBarController;
+
+// A C++ wrapper around an Objective-C InfoBarController.  This class
+// exists solely to be the return value for InfoBarDelegate::CreateInfoBar(),
+// as defined in chrome/browser/tab_contents/infobar_delegate.h.  This
+// class would be analogous to the various bridge classes we already
+// have, but since there is no pre-defined InfoBar interface, it is
+// easier to simply throw away this object and deal with the
+// controller directly rather than pass messages through a bridge.
+//
+// Callers should delete the returned InfoBar immediately after
+// calling CreateInfoBar(), as the returned InfoBar* object is not
+// pointed to by anyone.  Expected usage:
+//
+// scoped_ptr<InfoBar> infobar(delegate->CreateInfoBar());
+// InfoBarController* controller = infobar->controller();
+// // Do something with the controller, and save a pointer so it can be
+// // deleted later.  |infobar| will be deleted automatically.
+
+class InfoBar {
+ public:
+  InfoBar(InfoBarController* controller) {
+    DCHECK(controller);
+    controller_ = controller;
+  }
+
+  InfoBarController* controller() {
+    return controller_;
+  }
+
+ private:
+  // Pointer to the infobar controller.  Is never null.
+  InfoBarController* controller_;  // weak
+
+  DISALLOW_COPY_AND_ASSIGN(InfoBar);
+};
+
+#endif  // CHROME_BROWSER_COCOA_INFOBAR_H_